Tracer composition



. Patented Apr. 9, 1929.

UNITE oFHC TRACER COMPOSITION.

N 0 Drawing.

Application filed May 23, 1924. Serial No. 715,457.

(GRANTED UNDER THE ACT OF MARCH 3, 1L883, AS AMENDED APRE 30, 1928; 3700. G. 757.)

The invention described herein may be manufactured and used by or forthe Government or for governmental purposes withsults; the preferredelements for this purpose are thorium and cerium.

These elements may be used either in the form of a nitrate or otheroxygen carrier;

in the form of a fuel, as a sulpho-cyanates;

or in the form of inert substances merely for increasing the brilliance,as chloride.

in oxide or The following tracer mixtures'are typical examples ofdifferent uses of these elements: 40

As an oxygen carrier: I

out the a ent t e of n ro alt there- 5 on ym o m a y y y Strontiumnitrate- 60 p The subject of this invention 'is a com-' f mlimte 40bustible composition or mixture burning Thol'lmfl with greater or lessrapidity, as may be de- P sired, and possessing the desirable quality(1511011111? 25 10 of luminosity, brilliance, or visibility in an inertSubstance;

burning; the mixturebeing especially adap St ti it at w for use as atracer mixture in projectiles, S di i t 60 50 though also useful in manyother organiza- 40 tions, such as port fires, rockets, signal fires, cfg Oxide 15 and any burning composition in which the Thorium Oxide 10above mentioned qualities are desirable. C i 10 It has been found thatthe addition of certain rare earth elements to combustible The followlngare yp examples of materials will greatly increase the lumicombustiblemlxtlll'es 0f the S 20 noslty bnlhapcev and Vlslblhty thereofThorium-cerium salts 90 to 98 parts when combustion takes place Thesesame Thorium salts 2 to 10 v or elements, or proper salts thereof, whenthem- Thorium -alts '7' 90 to 98 selves combustible, may be used eitheralone Cerium n 2 to 10 or in combination with other elements for T n 25the purpose; above outlined. While the above mixtures are typical hileany rare earth element possessing tracer mixtures they are cited only byway the characteristics, when heated, of giving of example and areintended in no way to off an unusually large proportion of its limit theproportions of the various ingreenergy in the form of light Waves areadaptdients to those set forth as the proportions in 30 ed to producethe above outlined desired rewhich the thorium or cerium salts will beused depend largely upon the other ingredients mixed therewith and theuse to which 7 the mixture is intended to be put.

Having thus described the invention what is claimed is:

1. A non-explosive pyrotechnic composition including as elements saltsof thorium I and cerium and a binder.

2; A tracer composition for projectiles includingnitrates of analkali'earth metal, salts of cerium and thorium, a fuel and a binder.

3. A tracer composition for projectilesineluding nitrates of alkaliearth metals, an oxide of an alkali earth metal, salts of cerium andthorium a fuel and a binder.

4. A tracer composition for projectiles including nitrates of alkaliearth metals, an

oxide of an alkali earth metal, salts of rare earth metals a fuel and abinder.

5. A trader composition for projectiles including nitrates of an alkaliearth metal, sulphocyanates of cerium and thorium a fuel and a binder.

6. A tracer composition for projectiles including nitrates of an alkaliearth metal, salts of cerium and thorium and a fuel.

7 A tracer composition for projectiles, in-

eluding strontium nitrate 60 parts, mag- I nesium 40 parts, ceriumthorium salts, 41 parts, calcium resinate 45 parts.

HENRY G. PRITHAM.

